working memory model- Baddeley & Hitch

• Overview

  • Argued the model for the STM in MSM was too simplistic
  • Believed it was not a single store
  • Replaced STM with 'working memory' which is not a single store and its job is to temporarily store and manipulate information being used.
• Consists of:

  • Central executive
  • Visuo-spatial sketchpad
  • Phonological loop: articulatory loop and phonological store.
• Central Executive

  • Most important component
  • Responsible for monitoring and coordinating sub-systems (visuo-spatial sketchpad and phonological loop).
  • Not an information storage system
  • Decides which info should be attended to by WM and where it should be sent (verbal-phonological loop and visual- visuospatial sketchpad).
  • Directs attention and gives priority to specific activities.
• Phonological loop

  • Deals with verbal information (spoken and written material)
  • Consists of 2 parts; articulatory loop and phonological store.
• Phonological store

  • Linked to speech perception. Acts as an 'inner ear' and holds speech-based info for 1-2 seconds.
  • Spoken words enter phonological store directly
  • Written words must be converted into an articulatory (spoken) code before they can enter the phonological store.
• Articulatory loop

  • Linked to speech production and acts like an 'inner voice' rehearsing information from phonological store
  • Circulates info round and round like a tape loop
  • As long as we keep repeating it, we can retain the info in WM.
  • Also converts written material into an articulatory code and transfers it to phonological store.
• Visuo-spatial sketchpad

  • 'Inner eye' and deals with visual and spatial info
  • Plays an important role in helping us keep track of where we are in relation to other objects as we move through our environment
  • As we move around, our position in relation to objects is constantly changing and it is important that we can update this info.
• Limitations of WM

  • Evidence suggests that WM used 2 different systems for dealing with visual and verbal info
  • A visual processing task and verbal processing task can be performed at the same time
  • More difficult to perform 2 visual or 2 verbal tasks at the same time as they interfere with each other and performance is reduced. Supports idea that the phonological loop and sketch pad are separate systems.
• Episodic buffer

  • Updated by Baddeley in 2000 by adding the episodic buffer.
  • Acts as a 'back-up' store which communicates with both LTM and the components of the WM.
• Strengths

  • SE- KF brain damage caused him to have memory impairments for verbal info in STM, yet memory for visual was unaffected.
  • Supports idea that there are separate STM components for visual (visuo-spatial sketchap) and verbal (phonological loop) info in WMM.
• Strengths

  • Scientifically credible as Baddeley continued testing and improving model e.g. episodic buffer so hypothetico-deductive approach.
  • UA- practical advice to professionals who care for dementia patients. Help with daily routines, not performing 2 verbal tasks simultaneously as they interfere with each other e.g. don't listen to instructions whilst TV is on in the background.
• Weaknesses

  • RE- Liebermann, found blind people have excellent spatial awareness even though they don't have any visual info. So refutes idea that all spatial info is first visual. May be separate components.
  • AE- MSM claims for LTM to be created info must first enter SSTM and STM. So more complete explanation for memory, goes beyond STM.
  • Reductionist- isolates 2 sub-systems (phonological loop and visuo-spatial sketchpad). Ignores how info passes between sub-systems to LTM.